The sound made up of multiple voices of an angry mob or crowd, usually holding pitchforks, flaming torches, or picket signs. Usually followed by public speaker figure getting up on a podium and bringing everyone to order.

Croud:"RABBLE RABBLE RABBLE(etc)!!!!"
Randy Marsh:"We have to stop all these child abductions!"
Croud:"RABBLE RABBLE RABBLE!!!!"
Mayor:"It's not going to help the situation if all you people do is stand there and yell RABBLE RABBLE RABBLE!"
Croud:"RABBLE RABBLE RABBLE!!!"